Multi-conductor cable spacers for overhead transmission lines



Dec; 3, 1963 M. HoRovrrz 3,113,173

MULTI-CONDUCTOR CABLE SPACERS FOR OVERHEAD TRANSMISSION LINES Filed May 28, 1962 5 Sheets-Sheet 1 Dec. 3, 1963 M. HOROVlTZ 3,11

MULTI-CONDJCTOR CABLE SPACERS FOR OVERHEAD TRANSMISSION LINES Filed May 28, 1962 5 Sheets-Sheet. 2

4 e51 Wi ma.

Dec. 3, 1963 M. HOROVITZ 3,113,173

MULTI-coNDuc'roR CABLE SPACERS FOR OVERHEAD TRANSMISSION muss Filed May 28, 1962 5 She'ets-Sheet s Dec- 3, 1963 M. HoRovrrz 3,113 ;173

MULTI-CONDUCTOR CABLE SPACERS FOR OVERHEAD TRANSMISSION LINES Filed May 28, 1962 s Sheets-heet 4 Filed Ilay 2a, 1962 Dec. 3,; 963 M. HOROVITZ' 3,173

MULTI-CONDUCTOR CABLE SPACERS FOR OVERHEAD TRANSMISSION LINES 5 Sheets-Sheet 5 United States Patent 3,113,173 MULTi-CGNDUCTUR CABLE SPACERS F051 UVERHEAD Nfil'viiSfiiitlN LENES Marcus Horovitz, Leicester, England, assignor to Metatastik Limited, Leicester, England, a British company Fiied May 28, 1962, der. No. 198,134 illaims priority, application Great Britain lune ll, 1%

3 Claims. (Cl. fl b-40) This invention relates to spacers for holding apart the individual conductors of a multi-conduotor, electrical, overhead transmission line while permitting a certain degree of relative movement between the conductors, particularly in the lengthwise direction of the conductors, to allow for elongation of one conductor relative to another due to unequal stretch and for wind movement for exampie. The invention is concerned with a spacer for holding apart three or more conductors and particularly two pairs of two conductors arranged in a square or diamond formation or three pairs of two conductors arranged in a double square or diamond formation, and so on, as will hereinafter be more clearly explained.

An object of the invention is to provide a spacer for three or more conductors which permits relative movement of the conductors by hinging movements between conductor clamps and links inter-connecting the clamps but which is not subject to wear and any maintenance requirement at metal-to-nretal sliding surfaces.

A further object of the invention is to provide a spacer comprising a plurality of clamps one to grip each of the conductors to be spaced by the spacer, a plurality of straight, rigid spacing links, equal in number to the number of clamps, said links and clamps being arranged alternately in a closed geometrical figure with each link defining one side of the figure and being connected at its ends between jaw members of two clamps located at adjacent corners of the figure, at each end by a hinge joint comprising a rubber bush which by torsional shear deformation permits -a limited hinging movement of the link relative to the clamp jaw member about a hinge axis lying in the plane of the spacer and normal to the link.

Preferably, the rubber bushes are cylindrical.

However, if desired, the bushes may be part-spherical so as to allow limited universal movement between the links and the clamps by torsional shear deformation of the bushes.

Specific embodiments of the present invention will now be described, merely by way of example, with reference to the accompanying drawings whereof:

FIG. 1 is a plan view of an electrical, overhead transmission line provided with spacers according to the present invention,

FIG. 2 is a side view of a spacer as fitted to the transmission line of FIG. 1 and drawn to a larger size,

PEG. 3 is a partial view of the spacer shown in :FIG. 2 in part in cross-seotion and drawn to a still larger size to show details of construction,

FIG. 4 is a plan view of the spacer shown in FIG. 2, to a larger size, and in part in cross-section, to show further details of construction,

FIG. 5 is" a side view of a further spacer according to the present invention,

FIG. 6 is a partial side view of a still further spacer according to the present invention,

FIG. 7 is a side View of tlie spacer, part of which is shown in FIG. 6 but to a smaller size than in FIG. 6,

\FIG. 8 is a partial side view of a spacer according to the present invention, in part in section, and showing a modification,

FIG. 9 shows a modification of the spacer shown in FIGS. 2, '3 [and 4, and

FIG. 10 shows a further modification.

3,113,173- Patented Dec. 3, 1963 Referring to FIGS. 1 to 4, the transmission line comprises a series of pylons one of which is shown at 10 and each having horizontal arms 11 from which ceramic or glass insulators 12 hang all in well known manner, each to support, in the present example, a pair of electrical, overhead conductors, the conductors of each pair being disposed one below the other in a common vertical plane, there being two pairs of conductors on each side of the pylon. The upper conductors of each pair are indicated at 13 in FIG. 1, and with the arrangement in this figure it is necessary to maintain the conductors of each group of four conductors on each side of the pylon spaced mutually apart. This is done by spacers according to the invention, these being generally indicated at 14 in FIG. 1, the spacers being secured to the four cables on each side of the pylon at intervals along the length of the cables.

Each spacer 14', in the present example, comprises four rods or links 15 (see FlG. 2) each having, at each end, forked arms 1-6. The links are of equal length and arranged in square formation. Between the forked arms the links may be of any convenient cros-s seotional shape. In the present example they are of dumb-bell shape in cross-section as indicated in FIG. 3.

'Four clamps 17 are provided, one to grip each of the conductors, and adjacent ends of adjacent links 15 are connected to a diiferent one of the clamps. Thus hinged to each forked end of each link 15 is a clamp 17. Each clamp comprises parts l8, 19 (see FIG. 3) each of which forms one of the clamp jaws, the parts 18, 19 being hinged together by a hinge pin 22, the part #19, carrying hinged to it in a slot in its free end, an eye bolt 23 having screwed thereon a nut 24 provided, with a lock washer 25, to draw the clamp jaws together to grip a conductor 13 in the circular opening 26 defined between the parts "18, 19 when the eye bolt :23 is swung to engage in a slot in the part 1-8 and the nut 24 tightened.

The part 18 has a pair of lugs which project at right angles to one another to attach the part 18 to the adjacent ends of the adjacent links 15. The lugs 2t) are received between the forked arms 15 of the links and are connected to the forked arms by hinge joints 28 comprising cylindrical rubber bushes 29. The bushes 29 are a tight i.e. compression fit in bores in the lugs 20, between the bores and inner metal sleeves 3t tight fitted on bolts 27 which pass through the forked arms 16. The bushes 29 may be bonded to the lugs 20 or to the sleeves 30. The sleeves 30 have an axial extent greater than the bushes 29 and are gripped between the forked arms 16, the sleeves 30 and the bolts 27 being fixed i.e. non-rotatable with respect to the forked arms.

The bushes 29 are disposed with their cylindrical axes normal to the direction of the conductors 13 to permit angular movement of the clamps 17 relatively to the links 1% in torsion in the rubber. Considerable relative lengthwise movements of the conductors is therefore permitted whilst ensuring thatthe conductors are held apart by a minimum amount. The relative lengthwise movement may be due to unequal stretch in the conductors or to sideways movement of the conductors due to wind deflection. Changes in the relative length of two of the con ductors results in one conductor being raised vertical relatively to the other. If the conductors are horizontally spaced such movement is permitted in part by the rubber bushes 2% which are able to deflect conically to permit the bolts 27 to tilt in the bores in the lugs 20 to accommodate this relative movement.

Low amplitude vibration in the conductors, which is one of the main causes of wear at the joints of spacers and the cause of radio and television interference, is effectively catered for by the rubber bushes 29 which tend to damp out such vibrations.

Since relative movement of the conductors is provided for by distortion of the rubber bushes 2% and there is no relative sliding movement between metal parts of the hinge joints, it is unnecessary to lubricate the joints or provide for any maintenance thereof.

The resistance of the bushes 29 to distortion, particularly by relative lengthwise movements of the conductors which produces torsion of the rubber bushes, assists in returning the conductors to their undisplaced position when they are deflected by wind loads.

FIG. 5 shows a triangular arrangement of links for holding apart three conductors arranged in triangular formation, the spacer comprising three clamps 17 each end of each link 15 being connected to one of the clamps 11.7 by a hinge joint 28 as previously described, the lugs 20" on the clamps 17 being disposed at 60 to one another instead of at right angles like the lugs 24] previously described. i

The clamps shown in FIG. 6 for joining together the adjacent ends of three links 15 disposed two in line and one at right angles is for a spacer for three pairs or" two conductors as shown to a smaller scale in FIG. 7. The part 18" of the clamp 17 in this case has three lugs 20 to make the hinge joints 28 with the respective links 15.

The spacer shown in FIG. 7 is for the six conductors arranged in a double square formation, the clamps 17" at the ends of the common link 15 joining the central horizontally spaced pair of conductors in FIG. 7 being as shown in FIG 6, and the remaining clamps 17 being as shown in "FIG. 3. By using clamps as shown in FIG. 6 at the corners of the spacer as shown in FIG. 7 the spacer may be extended to hold apart 4, 5, 6 or more pairs of conductors as necessary.

The cylindrical rubber bushes 29 accommodate for limited universal movement between the clamps and the links. To provide for a greater degree of universal movement the hinge joints as described may be replaced by hinge joints as shown in FIG. 8. Here each of the bolts 27 carries, instead, a metal sphere-like inner element 31 which is enveloped in a layer of rubber 32 which is compressed by three separate parts 33 carried within a bore in the lug 20 and angularly spaced. Each part 33 has a part spherical inner surface and a part cylindrical outer surface. In effect each lug 20 constitutes a sleeve to hold the parts 33 together and pressed against the layer of rubber. The rubber may be bonded to the element 31 and/or to the parts 33. The parts 31, 32, 33 are assembled in the lugs 20 and the latter are then introduced to the forked ends of the links 15 and the bolts 27 are then inserted.

In yet another arrangement (not shown) each lug 20 comprises two cup portions having a joint face in a plane normal to the bolt 27, each part having a herni-spherical cavity within which a layer of rubber is compressed against a sphere-like inner element mounted on the bolt 27 when the two cup portions are assembled and drawn up. With this arrangement the forked ends of the links 15 are dispensed with and the bolts 27 project sideways from the links.

The bushes 29 previously described may be frustoconical instead of cylindrical if desired.

FIG. 9 shows a square arrangement of links 115 for holding apart four conductors 110, 111i, 112 and 113 arranged in square formation, the spacer comprising four clamps 117 one to grip each of the four conductors, the adjacent ends of adjacent links 115 both being connected to a dilferent one of the clamps each by a hinge joint 128 as previously described and comprising a cylindrical rubber bush 129 and an inner sleeve 130.

A diagonally opposite pair of the clamps 117 each has a jaw part 118 having in addition to a pair of lugs 12th at right angles and corresponding to the lugs 20 hereinbefore described a further pair of lugs 140 at 45 to the lugs 120. Extending between the lugs and connected thereto one at each end is a fifth link 141 extending diagonally in relation to the links 215. The link 141 is conneoted to the lugs 14% by hinge joints 145 corresponding with the hinge joints 23 previously described and comprising a cylindrical rubber bush 146 and an inner sleeve 147.

The link 114-1 acts to prevent the approach of the diagonally opposite pair of conductors III, 113. It also ties these conductors together diagonally and therefore, through t1 e spacing members 1115 prevents approach of the diagonally opposite pair of conductors 110, 1?.2. The link 141 therefore assists in holding the links 115 in square formation despite the flexible hinge joints 128, which by deformation of their rubber bushes 129 could permit the outline shape of the spacer to alter to a parallelogram form involving a substantial approach of a diagonally opposite pair of the conductors.

In FIG. 10 the diagonal link I4]. is replaced by a pair of cross-ties or braces 150 comprising flexible wires of metal, although nylon ropes or ropes of other synthetic plastic material could be used. The cross-ties have a central connector for four wires 152 screwed into the connector and into heads I53 like spoke heads screwed in sockets in the clamp parts 118.

The spacer shown in FIG. 7 may be cross-braced as shown in FIG. 8 or in FIG. 9 if desired. Where single diagonal links are employed the links preferably extend in parallel directions but they may extend at right angles to one another.

The hinge joints 128, 145 shown in FIG. 9 may in an alternative arrangement, be constructed as hereinbefore described with reference to and as shown in FIG. 8. Again they may be of the un-illustrated construction hereinbefore described.

I claim:

1. A spacer for use with a multi-conductor, electrical, overhead transmission line comprising a pattern of spaced conductors defining in cross-section the corners of a closed geometrical figure, the spacer comprising a plurality of clamps one to grip each of said conductors, each clamp presenting a first member including a jaw part, and a second member hinged to said first member and including a further jaw part to co-operate with said first jaw part to grip the conductor, and a plurality of straight, rigid spacing links, equal in number to the number of clamps, said links and clamps being arranged alternately in a closed geometrical figure corresponding with that of the conductors with each link defining one side of the figure and being connected at its ends between the first members of two clamps located at adjacent corners of the figure, at each end by a hinge joint comprising a rubber bush which by torsional shear deformation permits a limited hinging movement of the link relative to the clamp member about a hinge axis lying in the plane of the spacer and normal to the link.

2. A spacer as claimed in claim 1 for use with a multiconductor, electrical, overhead transmission line comprising four conductors, wherein four clamps and four links are provided, the links and clamps being arranged in quadrilateral configuration, the spacer further comprising a rigid, straight, diagonal link connected at its ends between the first members of two of the clamps located at diagonally opposite corners of the quadrilateral figure, at each end by a hinge joint comprising a rubber bush which by torsional shear deformation permits a limited hinging movement of the diagonal link relative to the clamp member about a hinge axis lying in the plane of the spacer and normal to the diagonal link. I

3. A spacer as claimed in claim 1, for use with a multiconductor, electrical, overhead transmission line comprising four conductors, wherein four clamps and four links are provided, the links and clamps being arranged in quadrilateral configuration, the spacer further comprising a pair of flexible, diagonally extending cross-ties one conr 3,113,173 l 5 i 6 nected at its ends between the first members of two of the References fitted in the file of this patent clamps located at one pair of diagonally opposite corners 4 A ENT of the quadrilatenal figure and the other connected at its FOFmGN P T S ends between the first members of the other two clamps 162,444 Austna Feb 1949 located at the other diagonally opposite pair of corners 5 788,076 Great Bfltaln 23, 1957 850,306 Germany Sept. 22, 1952 of the quadrilateral figure. 

1. A SPACER FOR USE WITH A MULTI-CONDUCTOR, ELECTRICAL, OVERHEAD TRANSMISSION LINE COMPRISING A PATTERN OF SPACED CONDUCTORS DEFINING IN CROSS-SECTION THE CORNERS OF A CLOSED GEOMETRICAL FIGURE, THE SPACER COMPRISING A PLURALITY OF CLAMPS ONE TO GRIP EACH OF SAID CONDUCTORS, EACH CLAMP PRESENTING A FIRST MEMBER INCLUDING A JAW PART, AND A SECOND MEMBER HINGED TO SAID FIRST MEMBER AND INCLUDING A FURTHER JAW PART TO CO-OPERATE WITH SAID FIRST JAW PART TO GRIP THE CONDUCTOR, AND A PLURALITY OF STRAIGHT, RIGID SPACING LINKS, EQUAL IN NUMBER TO THE NUMBER OF CLAMPS, SAID LINKS AND CLAMPS BEING ARRANGED ALTERNATELY IN A CLOSED GEOMETRICAL FIGURE CORRESPONDING WITH THAT OF THE CONDUCTORS WITH EACH LINK DEFINING ONE SIDE OF THE FIGURE AND BEING CONNECTED AT ITS ENDS BETWEEN THE FIRST MEMBERS OF TWO CLAMPS LOCATED AT ADJACENT CORNERS OF THE FIGURE, AT EACH END BY A HINGE JOINT COMPRISING A RUBBER BUSH WHICH BY TORSIONAL SHEAR DEFORMATION PERMITS A LIMITED HINGING MOVEMENT OF THE LINK RELATIVE TO THE CLAMP MEMBER ABOUT A HINGE AXIS LYING IN THE PLANE OF THE SPACER AND NORMAL TO THE LINK. 